The present invention relates, in general, to lead frames for semiconductor device packages, and more particularly, to a novel insulated lead frame for semiconductor device packages.
In the past, the semiconductor industry had used various types of packages for protecting semiconductor die. One particular type of package was a high power dissipation package that had an area suitable for attaching a heat sink. On the package's top side, a ceramic cap usually covered a semiconductor die that was attached to the package's lead frame. The back side of the package typically had an electrically insulating material mounted opposite the die attach area, and a metal or other type heat sink attached to the electrical insulator. Because of its high thermal conductivity, beryllium oxide (BeO) was often used as the insulating material. Since beryllium oxide was a hazardous material, it required very careful handling during the various operations required to assemble the package. Such special handling increased the package's manufacturing cost. Generally, piece parts for the package were very expensive and were not compatible with automated assembly equipment for semiconductor packages thereby further increasing the package's manufacturing costs.
Accordingly, it is desirable to have a semiconductor package with an insulated lead frame that has a low cost, that is compatible with automated manufacturing equipment, and that does not use hazardous materials.